Accommodating existing traffic is a key priority when ADOT builds a freeway … Depending on the project, that can mean working out a construction schedule that takes rush hours into account or hiring extra crews to flag and direct traffic through the site.

Last month, as part of our Building a Freeway series, we told you about the massive underground support substructures that help give bridges strength. Next up in the series is an important -- but temporary -- structure that’s used as crews build a bridge, tunnel or even a box culvert.